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%I #19 Jan 31 2020 12:06:17
%S 1,2,3,12,16,47,314
%N Numbers k such that the sum of the first k palindromes is a palindrome.
%H Patrick De Geest, <a href="http://www.worldofnumbers.com/index.html">World!Of Numbers</a>
%e a(n)=47 so 1+2+3+...+373+383 (47 terms) = 7557.
%t palQ[n_] := Reverse[x = IntegerDigits[n]] == x; t = Select[Range[25000], palQ[#] &]; Flatten[Rest[Position[Accumulate[t], _?palQ]]] (* _Jayanta Basu_, Jun 26 2013 *)
%t Position[Accumulate[Select[Range[100000],PalindromeQ]],_?PalindromeQ] // Flatten (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jan 31 2020 *)
%Y Cf. A002113, A046487, A046488.
%K nonn,hard,base
%O 1,2
%A _Patrick De Geest_, Sep 15 1998
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